Alright, let's work through 6444 times 3507 step by step
6444 × 3507 = 3507 × (6444)
+ 3507 × 4 that equals 14028
+ 3507 × 40 that results in 140280
+ 3507 × 400 which equals 1402800
+ 3507 × 6000 giving us 21042000

= 22599108
